<template>
  <div>
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>分类参数</el-breadcrumb-item>
    </el-breadcrumb>

    <el-card>
      <!-- 头部警告区域 -->
      <el-alert title="注意: 只允许为三级分类设置相关参数!" type="warning" :closable="false" show-icon>
      </el-alert>
      <!-- 选择商品分类 -->
      <el-row class="cat_opt">
        <el-col>
          <span>选择商品分类: </span>
          <!-- 选择商品分类的级联选择框 -->
          <el-cascader v-model="selectedKeys" :options="cateList" :props="cateProps" clearable expand-trigger="hover"
            @change="handleChange"></el-cascader>
        </el-col>
      </el-row>

      <el-tabs v-model="activeName" @tab-click="handleTabClick">
        <el-tab-pane label="动态参数" name="many">
          <el-button :disabled="isBtnDisabled" size="mini" type="primary" @click="addDialogVisible = true">添加参数
          </el-button>

          <!-- 动态参数表格 -->
          <el-table :data="manyTableData" border element-loading-text="拼命加载中" stripe>
            <el-table-column type="expand">
              <!-- 作用域插槽-->
              <template slot-scope="scope">
                <!-- 循环渲染Tag标签 -->
                <el-tag v-for="(item, i) in scope.row.attr_vals" :key="i" closable @close="handleClose(i, scope.row)">
                  {{ item }}
                </el-tag>
                <!-- 输入的文本框-->
                <el-input v-if="scope.row.inputVisible" ref="saveTagInput" v-model="scope.row.inputValue"
                  class="input-new-tag" size="small" @blur="handleInputConfirm(scope.row)"
                  @keyup.enter.native="handleInputConfirm(scope.row)">
                </el-input>
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag
                </el-button>
              </template>
            </el-table-column>
            <!--索引列-->
            <el-table-column label="#" type="index"></el-table-column>
            <el-table-column label="参数名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button icon="el-icon-edit" size="mini" type="primary" @click="showEditDialog(scope.row)">编辑
                </el-button>
                <el-button icon="el-icon-delete" size="mini" type="danger" @click="removeParams(scope.row.attr_id)">删除
                </el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>

        <!-- 静态属性 -->
        <el-tab-pane label="静态属性" name="only">
          <el-button :disabled="isBtnDisabled" size="mini" type="primary"
            @click="addDialogVisible = true">添加参数</el-button>
          <!-- 静态属性表格 -->
          <el-table :data="onlyTableData" border element-loading-text="拼命加载中" stripe>
            <!--展开行-->
            <el-table-column type="expand">
              <!-- 作用域插槽-->
              <template slot-scope="scope">
                <!-- 循环渲染Tag标签 -->
                <el-tag v-for="(item, i) in scope.row.attr_vals" :key="i" closable @close="handleClose(i, scope.row)">
                  {{ item }}
                </el-tag>
                <!-- 输入的文本框-->
                <el-input v-if="scope.row.inputVisible" ref="saveTagInput" v-model="scope.row.inputValue"
                  class="input-new-tag" size="small" @blur="handleInputConfirm(scope.row)"
                  @keyup.enter.native="handleInputConfirm(scope.row)">
                </el-input>
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag
                </el-button>
              </template>
            </el-table-column>
            <!--索引列-->
            <el-table-column label="#" type="index"></el-table-column>
            <el-table-column label="属性名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button icon="el-icon-edit" size="mini" type="primary" @click="showEditDialog(scope.row)">编辑
                </el-button>
                <el-button icon="el-icon-delete" size="mini" type="danger" @click="removeParams(scope.row.attr_id)">删除
                </el-button>
              </template>
            </el-table-column>
          </el-table>

        </el-tab-pane>
      </el-tabs>
    </el-card>
    <!-- 添加静态/动态参数对话框 -->
    <el-dialog :title="'添加' + titleText" :visible.sync="addDialogVisible" width="50%" @close="addFormClosed">
      <el-form ref="addFormRef" :rules="addFormRules" :model="addForm" label-width="80px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="addForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="addDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="addParams">确 定</el-button>
      </span>
    </el-dialog>

    <!-- 修改静态/动态参数对话框 -->
    <el-dialog :title="'添加' + titleText" :visible.sync="editDialogVisible" width="50%" @close="editFormClosed">
      <el-form ref="editFormRef" :rules="editFormRules" :model="editForm" label-width="80px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="editDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="editParams">确 定</el-button>
      </span>
    </el-dialog>
  </div>
</template>

<script>
export default {
  data() {
    return {
      // 商品分类列表
      cateList: [],
      // 级联选择框双向绑定到的数组
      selectedKeys: [],
      cateProps: {
        value: 'cat_id',
        label: 'cat_name',
        children: 'children',
        expandTrigger: 'hover'
      },
      // 被激活的页签的名称
      activeName: 'many',
      // 动态参数的数据
      manyTableData: [],
      // 静态参数的数据
      onlyTableData: [],
      // 控制添加参数的显示隐藏
      addDialogVisible: false,
      // 添加参数数据
      addForm: {
        attr_name: ''
      },
      addFormRules: { attr_name: [{ required: true, message: '请输入参数', trigger: 'blur' }] },
      // 控制修改参数的显示隐藏
      editDialogVisible: false,
      editFormRules: { attr_name: [{ required: true, message: '请输入参数', trigger: 'blur' }] },
      // 修改参数数据
      editForm: { attr_name: '' }
    }
  },
  created() {
    this.getCategories()
  },
  methods: {
    // 获取所有商品列表
    async getCategories() {
      const { data: res } = await this.$http.get('categories')
      if (res.meta.status !== 200) {
        this.$message.error('获取商品分类失败!')
      }
      this.cateList = res.data
      console.log(this.cateList)
    },
    // 当级联选择框数据变化触发
    handleChange() {
      this.getParamsData()
    },
    // tab页面点击事件的处理函数
    handleTabClick() {
      this.getParamsData()
    },
    // 获取参数的列表数据
    async getParamsData() {
      // 如果选择的不是三级分类,数据表格清空
      if (this.selectedKeys.length !== 3) {
        this.selectedKeys = []
        this.manyTableData = []
        this.onlyTableData = []
        return
      }
      // console.log(this.selectedKeys)
      const { data: res } = await this.$http.get(`categories/${this.cateId}/attributes`, {
        params: { sel: this.activeName }
      })
      if (res.meta.status !== 200)
        return this.$message.error('获取参数列表失败')
      console.log(res.data)
      res.data.forEach(item => {
        // 三元表达式
        item.attr_vals = item.attr_vals ? item.attr_vals.split(' ') : []
        // 控制输入框与按钮的切换形式
        item.inputVisible = false
        // 文本框中输入的值
        item.inputValue = ''
      })

      // 区分请求是动态还是静态的数据
      if (this.activeName === 'many') {
        this.manyTableData = res.data
      } else {
        this.onlyTableData = res.data
      }
    },
    // 监听添加对话框的关闭事件
    addFormClosed() {
      this.$refs.addFormRef.resetFields()
    },
    // 点击按钮, 添加参数
    addParams() {
      this.$refs.addFormRef.validate(async valid => {
        if (!valid) {
        } else {
          const { data: res } = await this.$http.post(`categories/${this.cateId}/attributes`, {
            attr_name: this.addForm.attr_name,
            attr_sel: this.activeName
          })
          if (res.meta.status !== 201) {
            return this.$message.error('添加参数失败!')
          } else {
            this.getParamsData()
            this.addDialogVisible = false
            return this.$message.success('添加参数成功!')
          }
        }
      })
    },
    // 点击编辑，显示修改对话框
    async showEditDialog(row) {
      const { data: res } = await this.$http.get(`categories/${this.cateId}/attributes/${row.attr_id}`,
        { params: { attr_sel: this.activeName } })
      if (res.meta.status !== 200)
        return this.$message.error('获取参数信息失败')
      this.editForm = res.data
      console.log(this.editForm)
      this.editDialogVisible = true

    },
    // 监听修改对话框的关闭事件
    editFormClosed() {
      this.$refs.editFormRef.resetFields()
    },
    // 点击按钮, 修改参数
    editParams() {
      this.$refs.editFormRef.validate(async valid => {
        if (!valid) {
          return this.$message.error('校验不通过, 请重新输入')
        } else {
          const { data: res } = await this.$http.put(`categories/${this.cateId}/attributes/${this.editForm.attr_id}`, {
            attr_name: this.editForm.attr_name,
            attr_sel: this.activeName
          })
          if (res.meta.status !== 200) {
            return this.$message.error('更新参数失败!')
          } else {
            this.editDialogVisible = false
            this.getParamsData()
            return this.$message.success('更新参数成功!')
          }
        }
      })
    },
    // 根据Id删除对应的参数/属性
    async removeParams(attrId) {
      // 弹框询问用户是否删除数据
      const confirmResult = await this.$confirm(`此操作将永久删除该${this.titleText}, 是否继续?`, '提示', {
        confirmButtonText: '确定',
        cancelButtonText: '取消',
        type: 'warning'
      }).catch(err => err)
      if (confirmResult !== 'confirm') {
        return this.$message.info('已取消删除!')
      }
      const { data: res } = await this.$http.delete(`categories/${this.cateId}/attributes/${attrId}`)
      if (res.meta.status !== 200) {
        return this.$message.error(`删除${this.titleText}失败!`)
      } else {
        this.getParamsData()
        return this.$message.success(`删除${this.titleText}成功!`)
      }
    },
    // 文本框失去焦点, 或按下enter都会触发
    handleInputConfirm(row) {
      if (row.inputValue.trim().length === 0) {
        row.inputVisible = false
        row.inputValue = ''
        return
      }
      // 如果没有return, 这里证明输入的内容, 需要做后序处理
      row.attr_vals.push(row.inputValue.trim())
      row.inputValue = ''
      row.inputVisible = false
      // 发起请求, 保存这次操作
      this.saveAttrVals(row)
    },

    //  点击按钮, 展示文本输入框
    showInput(row) {
      row.inputVisible = true
      // 让文本框自动获取焦点
      // $nextTick方法的作用, 就是放页面上元素被重新渲染之后, 才会指定回调函数中的代码(即按钮变完文本框之后)
      this.$nextTick(_ => {
        this.$refs.saveTagInput.$refs.input.focus()
      })
    },
    // 将对 attr_vals的操作保存到数据库
    async saveAttrVals(row) {
      const { data: res } = await this.$http.put(`categories/${this.cateId}/attributes/${row.attr_id}`, {
        attr_name: row.attr_name,
        attr_sel: this.activeName,
        attr_vals: row.attr_vals.join(' ')
      })
      if (res.meta.status !== 200) {
        return this.$message.error('修改参数项失败!')
      } else {
        this.$message.success('修改参数项成功!')
      }
    },
    // 删除tag标签
    handleClose(index, row) {
      row.attr_vals.splice(index, 1)
      this.saveAttrVals(row)
    }
  },
  computed: {
    isBtnDisabled() {
      return this.selectedKeys.length !== 3
    },
    cateId() {
      if (this.selectedKeys.length === 3) {
        return this.selectedKeys[2]
      }
      return null
    },
    titleText() {
      return this.activeName === "many" ? '动态参数' : '静态参数'
    }
  }

}
</script>

<style lang="less" scoped>
.cat_opt {
  margin: 20px 0;
}

.el-table {
  margin-top: 20px;

  .el-tag {
    margin: 0 8px;
  }

  .el-tag:first-of-type,
  .button-new-tag {
    margin-left: 50px;
  }

  .input-new-tag {
    margin-left: 50px;
    width: 80px;

  }

  .el-tag:first-of-type~.button-new-tag {
    margin-left: 8px;
    height: 32px;
    line-height: 30px;
    padding-top: 0;
    padding-bottom: 0;
  }

  .el-tag:first-of-type~.input-new-tag {
    width: 80px;
    margin-left: 10px;
    vertical-align: bottom;
  }
}
</style>